The present invention relates to optical telecommunication techniques. More particularly, the present invention provides a wavelength locker integrated in silicon photonics transmission system.
Over the last few decades, the use of communication networks exploded. In the early days Internet, popular applications were limited to emails, bulletin board, and mostly informational and text-based web page surfing, and the amount of data transferred was usually relatively small. Today, Internet and mobile applications demand a huge amount of bandwidth for transferring photo, video, music, and other multimedia files. For example, a social network like Facebook processes more than 500 TB of data daily. With such high demands on data and data transfer, existing data communication systems need to be improved to address these needs.
Progress in computer technology (and the continuation of Moore's Law) is becoming increasingly dependent on faster data transfer between and within microchips. Optical interconnects may provide a way forward, and silicon photonics may prove particularly useful, once integrated on the standard silicon chips. 40-Gbit/s and then 100-Gbit/s data rates WDM optical transmission over existing single-mode fiber is a target for the next generation of fiber-optic communication networks. The big hangup so far has been the fiber impairments like chromatic dispersion that are slowing the communication signal down. Everything is okay up to 10 Gbits/s plus a little, but beyond that, distortion and attenuation take their toll. Many approaches are proposed on modulation methods for transmitting two or more bits per symbol so that higher communication rates can be achieved. Beyond the light modulation for data transmission, the MUX/DEMUX of light signals is another one of essential building blocks for the optical communication network. All these network building blocks integrated on silicon chips as silicon photonic devices have many advantages over conventional stand-alone optical and electrical devices.
In particular, silicon photonic devices have been applied in dense-wavelength-division multiplexing (DWDM) optical transmission networks, in which DEMUX/MUX of light signals require precise wavelength targeting and control over environment temperature change. Therefore, improved silicon photonics wavelength locking techniques and devices are desired.